George Russell and Lewis Hamilton managed to put their cars in second and third respectively during Friday qualifying.
Despite a poor sprint qualifying for Hamilton, they took home a decent points haul during Saturday's sprint race, increasing their gap to Ferrari in the battle for second place in the constructors' championship.
After the race, Leclerc spoke to Sky Sports about his team's performance.
“I don't know what to think about Mercedes," he said.
"After the accident Russell went very fast and I can't explain it. Throughout the weekend we struggled more than expected, especially in the race.
"A shame, the car didn't go well in the first stint, better in the second and third"
Ferrari looking over their shoulders
All of the talk since the summer break has been about the battle between Mercedes and Ferrari for the title of being 'best of the rest'.
With Red Bull wrapping up both the constructors' title and the drivers' championship with Max Verstappen, the focus for Ferrari is to get back up into contention for regular race wins.
However, it is McLaren who have been the closest to Red Bull in recent races, and Sunday's grand prix produced their second double-podium finish in a row.
On top of this, Oscar Piastri also managed to win the sprint race, ensuring a huge points haul for the team which might just have Ferrari looking behind them in the constructors' standings, rather than ahead.
“McLaren is very strong, very, very strong," Leclerc continued.
"I think we expected them to be strong, not as strong as what we’ve seen this weekend. We also expect to be much closer in some of the tracks until the end of the year, so it’s not time to give up whatsoever.
"They are getting closer, for sure. We need to keep pushing. There will be races where we are more in the game, others where we will be struggling, especially these kind of tracks with high speed corners."